低温喹啉降解菌的筛选及降解性能

Screening of quinoline-degradation bacteria and their biodegradation capability at low temperature

从吉林石化污水处理厂的活性污泥中驯化、筛选获得一株降解效率高且生长速率快高效耐冷菌,命名为WS-5。该菌能以喹啉作为惟一的碳源、氮源及能源。结合菌体的形态观察、生理生化特性实验及16S rDNA序列同源性对比分析,鉴定菌株WS-5为恶臭假单胞菌(Pseudomonas putida)。不同降解条件下的实验结果表明,菌株WS-5的最佳降解条件是投菌量为15%,pH值范围在8～10,摇床转速为100 r/min。最佳降解环境下对200 mg/L的喹啉在132 h降解率达到了85.3%。菌株WS-5对初始喹啉浓度为50、100、200和300 mg/L的初始喹啉浓度分别在36、72、192和262 h内完全降解。这将为今后在低温条件下处理含喹啉废水提供技术指导。

One strain of psychrophilic bacteria （named as WS-5） which biodegrades quinoline efficiently and grows at a high speed was domesticated and screened from activated sludge of a petrochemical industry sew- age treatment plant in Jilin. Strain WS-5 was able to utilize quinoline as a sole source of carbon, nitrogen and energy. It was identified as Pseudomonas putida which combined the morphology and physiological biochemical characteristics with the comparative analysis of 16S rDNA sequence. The experimental results under different conditions show that the optimal conditions for the degradation of quinoline of strain WS-5 were as follows ： the a- mount inoculation of 15% ; the pH value of 8 - 10 ; and the shaker rotary speed of 100 r/min. Under the best biodegradation conditions, the degradation rate of quinoline of 200 mg/L reached 85.3% during the period of 132 hours. Quinoline, whose initial concentrations of 50, 100, 200 and 300 mg/L, was completely biodegraded by Strain WS-5, in the time of 36, 72, 192 and 262 h, respectively. This research will provide technical guid- ance for treating quinoline sewage at low temperature in the future.